Package org.apache.hadoop.hbase.master.balancer

Class PrimaryRegionCountSkewCostFunction

java.lang.Object

org.apache.hadoop.hbase.master.balancer.CostFunction

org.apache.hadoop.hbase.master.balancer.PrimaryRegionCountSkewCostFunction

@Private
class PrimaryRegionCountSkewCostFunction
extends CostFunction

Compute the cost of a potential cluster state from skew in number of primary regions on a cluster.

Field Summary

Fields

Modifier and Type	Field	Description
private final DoubleArrayCost	cost
private static final float	DEFAULT_PRIMARY_REGION_COUNT_SKEW_COST
private static final String	PRIMARY_REGION_COUNT_SKEW_COST_KEY

Fields inherited from class org.apache.hadoop.hbase.master.balancer.CostFunction

cluster, COST_EPSILON

Constructor Summary

Constructors

Constructor	Description
PrimaryRegionCountSkewCostFunction(org.apache.hadoop.conf.Configuration conf)

Method Summary

Modifier and Type	Method	Description
private double	computeCostForRegionServer(int regionServerIndex)
protected double	cost()
(package private) boolean	isNeeded()
(package private) void	prepare(BalancerClusterState cluster)	Called once per LB invocation to give the cost function to initialize it's state, and perform any costly calculation.
protected void	regionMoved(int region, int oldServer, int newServer)

Methods inherited from class org.apache.hadoop.hbase.master.balancer.CostFunction

getMultiplier, postAction, scale, setMultiplier, updateWeight

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

PRIMARY_REGION_COUNT_SKEW_COST_KEY

private static final String PRIMARY_REGION_COUNT_SKEW_COST_KEY

See Also:

• Constant Field Values

DEFAULT_PRIMARY_REGION_COUNT_SKEW_COST

private static final float DEFAULT_PRIMARY_REGION_COUNT_SKEW_COST

See Also:

• Constant Field Values

cost

private final DoubleArrayCost cost

Constructor Details

PrimaryRegionCountSkewCostFunction

PrimaryRegionCountSkewCostFunction(org.apache.hadoop.conf.Configuration conf)

Method Details

computeCostForRegionServer

private double computeCostForRegionServer(int regionServerIndex)

prepare

void prepare(BalancerClusterState cluster)

Description copied from class: CostFunction

Called once per LB invocation to give the cost function to initialize it's state, and perform any costly calculation.

Overrides:

prepare in class CostFunction

regionMoved

protected void regionMoved(int region,
 int oldServer,
 int newServer)

Overrides:

regionMoved in class CostFunction

isNeeded

boolean isNeeded()

Overrides:

isNeeded in class CostFunction

cost

protected double cost()

Specified by:

cost in class CostFunction